Microstructural evolution of MCrAlX-coated Ni-based superalloy systems

Industrial gas turbine blades are typically made from coated Ni-based superalloys for power generation plant. The operation environments for these blades are very aggressive, comprising high temperatures (> 900°C) and potential chemical contaminants leading to oxidation and corrosion. An MCrAlX (where M is Ni and/or Co) coating is usually applied directly on the top of the alloy surface and forms an oxide scale (typically alumina) that can protect the substrate against further oxidation. However, it is widely accepted that the current generation of MCrAlX coatings only provide limited protection and need significant improvement. [Continues.]